Find two numbers consisting of 3 or 5 digits, and that these figures in the number are all odd or even

Numbers

import java.util.ArrayList;
import java.util.List;

public class Numbers {

    public static void main(String[] args) {
        int[] numbers = { 95017, 12059, 594, 524, 867, 777, 192, 93707, 51489, 43046, 25, 66, 68240 };

        List<Integer> answers = new ArrayList<>();
        // Answer: 777, 68240

        for (int number : numbers) {
            int copyNumber = number;

            int length = length(number);
            if (length == 3 || length == 5) {

                Boolean findingEven = null;
                boolean isSuitable = true;

                while (number > 0) {
                    int digit = number % 10;

                    if (digit % 2 == 0) {
                        if (findingEven == null || findingEven) {
                            findingEven = true;
                            number = number / 10;
                        } else {
                            isSuitable = false;
                            break;
                        }
                    } else {
                        if (findingEven == null || !findingEven) {
                            findingEven = false;
                            number = number / 10;
                        } else {
                            isSuitable = false;
                            break;
                        }
                    }
                }

                if (isSuitable) {
                    answers.add(copyNumber);
                }
            }
        }

        System.out.println(answers);
    }

    // Optimal method for speed and memory
    private static int length(int number) {
        if (number < 100000) {
            if (number < 100) {
                if (number < 10) {
                    return 1;
                } else {
                    return 2;
                }
            } else {
                if (number < 1000) {
                    return 3;
                } else {
                    if (number < 10000) {
                        return 4;
                    } else {
                        return 5;
                    }
                }
            }
        } else {
            if (number < 10000000) {
                if (number < 1000000) {
                    return 6;
                } else {
                    return 7;
                }
            } else {
                if (number < 100000000) {
                    return 8;
                } else {
                    if (number < 1000000000) {
                        return 9;
                    } else {
                        return 10;
                    }
                }
            }
        }
    }


}